1. Field of the Invention
The present invention relates to an image processing apparatus, an image processing method and a program.
2. Description of the Related Art
A conventional reproduction method of gradation is disclosed in Japanese Patent Laid-Open No. 2007-66070. In the method according to Japanese Patent Laid-Open No. 2007-66070, it is determined whether or not a gradation region is in a direction where pixels are connected for each line in a horizontal direction in a bit map image. In a case where a given condition is met, an average changing rate of the concentrations of pixels included in the region is calculated to produce a gradation expression image.
In the conventional method, as in the case of the dark and light expression inside a stroke of a handwritten character, it is not possible to detect a location where a parameter of gradation is uneven in a closed region after vectorization.
In addition, after detecting the pattern of the gradation, it is not possible to describe the gradation in vectorization.